Lysozyme, a protein discovered by Fleming in 1922, is found in all living organisms (plants, animals, bacteria, algae, fungi, etc.). Its activity occurs at the membrane level of numerous bacteria, in particular those which are gram-positive. In higher animals, it represents a natural immunity factor in the defence against infection. Apart from its own lytic activity, lysozyme is able to potentiate the action of numerous antibiotics, micro-organisms partially lysed by lysozyme becoming more sensitive to antibiotics.
Another characteristic of lysozyme is its beneficial influence on the digestive processes in mammals which is manifested by prompt normalisation of the intestinal flora, with consequent saving or improvement of the nitrogen metabolism.
Although found in both the animal and plant kingdoms, lysozyme is currently produced on an industrial scale exclusively by extracting from egg white.
We have recently carried out test studies with lysozyme in chickens to combat some of the diseases more frequently seen and to observe any effect on growth.
As is known, chickens are usually vaccinated by aerosols three times in their lives in order to prevent pathological developments. However, 48 hours after vaccination, symptoms of stress appear and the birds fall into a state of prostration with loss of appetite and, consequently, interruption of growth. In order to prevent this debility, antibiotic treatment is given to the birds 36 hours after vaccination. In most cases, this treatment gives positive results. However, as is known, antibiotics can cause the development of resistant strains and when this treatment is used in combating certain forms of respiratory diseases, the results obtained are ineffective because of the resistant bacterial forms present in the diseased chickens.
As a result of our trials, we have found that, in combating vaccination stress with lysozyme, there were two advantages:
(1) the antibiotic dose could be lowered and PA0 (2) the antibiotics could frequently be eliminated altogether so that they need only be used to combat bronchopulmonary diseases when such diseases appear. PA0 1st group: 2.314 kg. PA0 2nd group: 2.541 kg. PA0 3rd group: 2.639 kg. PA0 4th group: 2.607 kg.